That was a stupid optimization.

Processes can be reordered, so count is not a guarantee here at all.

diff --git a/src/smpi/mpi/smpi_group.cpp b/src/smpi/mpi/smpi_group.cpp
index a4e1738..b3916ed 100644 (file)
--- a/src/smpi/mpi/smpi_group.cpp
+++ b/src/smpi/mpi/smpi_group.cpp
@@ -111,10 +111,6 @@ int Group::incl(int n, const int* ranks, MPI_Group* newgroup)
 {
   if (n == 0) {
     *newgroup = MPI_GROUP_EMPTY;
-  } else if (n == size_) {
-    *newgroup = this;
-    if (this != MPI_COMM_WORLD->group() && this != MPI_COMM_SELF->group() && this != MPI_GROUP_EMPTY)
-      this->ref();
   } else {
     *newgroup = new Group(n);
     for (int i = 0; i < n; i++) {